The mind can quickly create feelings of joy or pain, which have virtually no connection with the long time effects of what we do.
Meditation (and its recent love child with science, brainwave entrainment) is not a matter of belief. It is a matter of experience. I will comment today on some of these experiences and their time frame, which is very different for each perspective: Mind, body and spirit.
When you sit down and shut up for the first time, your MIND will release a surge of unbound awareness. If you sit in a quiet place with your eyes closed, that awareness will not be able to attach itself to sights and sounds, but will instead rush to attach to objects of the mind: Thoughts, emotions, memories, bodily sensations. These experiences are then drawn to the mind by free awareness, and will seem magnified because they are not drowned out by the usual activity of the mind. They can be pleasant, or unpleasant, or just plain weird. But by and large they will be somehow unusual. And one thing more: They will all pass. Some will fade as soon as you end the session, but in any case a regular practice of meditation will withdraw attachment and at the very least they will fade then.
This means a double threat to the casual would-be meditator. If the first experience is painful or frightening, you will not want to do it again at all. But if the first experience is pleasurable, then when it starts fading you will be upset and disappointed. Most likely you will then move on to some alternative technique, hoping to get that first rush of goodness again. In either case you fail to reap the benefits of a regular meditation practice.
While the mind acts literally in the blink of an eye, the body adapts more slowly. When you have a new experience of any kind, the brain will start growing new connections. The more unusual the experience, the more new connections in the brain. For most people, just sitting down and shutting up is a truly alien experience at first. If you used brainwave entrainment you will quickly experience some degree of synchronization between the two hemispheres of the brain, which should encourage growth of connections between these two halves. (With unaided meditation, this will happen somewhat later and more gradually.) It is not a good idea to overdose on these things, as I have reported elsewhere. It can cause seriously trippy side effects that can even be similar to psychoactive drugs, or at the very least weird and sometimes scary dreams.
The changes in the brain start within hours and continue for several weeks as the new connections grow and mature. After this they will be maintained for a while, but will slowly become more permanent and continue to grow if you repeat your practice regularly. After decades of meditation, there are large visible changes to the brain, with some parts of the brain being visibly larger and having more gray matter than in people who don’t meditate (or pray, or chant, etc) habitually. But long before this you should be able to notice that you are more emotionally stable, thinking more clearly, learning easier and sleeping better (albeit not necessarily more). Stress related illnesses will have less and less power over you. Eventually your mental health will reach a level where you see some of your past habits and thought patterns as sheer insanity.
As you can see, there is no real connection between the first rush of experience when you try meditation (or brainwave entrainment) and the lasting benefits after years of practice. The first is just a rush of new experience; the latter is a fundamental change of who you are in this world. If you just keep repeating your mantra, or count slowly to four, or chant the Holy Name, or listen to the binaural sound track, you will change. More exactly, because meditation is a natural part of human life (despite being repressed in some cultures), you will change into who you were meant to be. More about that “natural part” thing in our next update, Light willing.